The 4 Masks shader.
This Shader allows you to use the 4 channels of RGBa to mask out your Diffuse, Normals, specular and Emissive.
You can now have a mesh supported by one material having 4 different look possibilities
If you like this shader you can buy a complete pack with awesome shader called Pro Shaders in the store!
To see the shaders in actions have a look at this link.